01 - Preheat oven to 350°F (175°C). Line a 12-cup muffin tin with paper liners or grease lightly with oil.
02 - In a large mixing bowl, whisk together the all-purpose flour, matcha green tea powder, baking soda, baking powder, and salt until evenly distributed.
03 - In a separate bowl, combine the mashed bananas, granulated sugar, eggs, melted coconut oil, coconut milk, and vanilla extract. Mix until smooth and well incorporated.
04 - Pour the wet ingredient mixture into the dry ingredients. Stir gently until just combined—do not overmix to keep the muffins tender.
05 - Gently fold in the unsweetened shredded coconut and chopped walnuts or pecans if using, distributing evenly throughout the batter.
06 - Divide the batter evenly among the prepared muffin cups, filling each about three-quarters full.
07 - Bake for 18 to 22 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
08 - Allow the muffins to cool in the pan for 5 minutes, then transfer to a wire cooling rack to cool completely before serving.